The Hakkōda Tunnel (八甲田トンネル, Hakkōda tonneru) is a 26.445-kilometer-long (16.432 mi) railway tunnel located in central Aomori Prefecture, in the Tōhoku region of Japan. It passes through the Hakkōda mountain range and links the town of Shichinohe with the city of Aomori.

Hakkōda Tunnel
The western portal of the Hakkōda Tunnel
Overview
Official nameJapanese: 八甲田トンネル
LineTōhoku Shinkansen
LocationJapan (Aomori Prefecture)
Coordinates40°46′44.6″N 140°55′49.7″E / 40.779056°N 140.930472°E / 40.779056; 140.930472
SystemShinkansen
CrossesHakkōda Mountains
StartShichinohe
EndAomori
Operation
Work begunAugust 1998
Opened19 November 2010
OwnerJR East
TrafficShinkansen
CharacterPassenger
Technical
Length26.445 km (16.432 mi)
No. of tracks1 double-track tube
Track gauge1,435 mm (4 ft 8+12 in)
Electrified25 kV AC, 50 Hz, overhead catenary
Operating speedMaximum speed: 260 km/h (160 mph)
Grademax 10 ‰

The Hakkōda Tunnel is part of the northern section of the Tōhoku Shinkansen, located between Shichinohe-Towada and Shin Aomori stations.

Description

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The Hakkōda Tunnel, with a length of 26.445 kilometers (16.432 mi) is the third longest double-tracked, single-tube terrestrial railway tunnel in the world and the longest terrestrial railway tunnel in Japan, though the Oshima Tunnel in southern Hokkaido is set to surpass it upon its planned completion in 2031.[1] It is also the first rail route to pass through the Hakkōda Mountains.

The east portal of the tunnel lies 5 kilometers (3.1 mi) from Shichinohe-Towada Station in Shichinohe. From there the tunnel runs parallel to the Michinoku Toll Road, an older limited-access road that travels across the northern Hakkōda Mountains by a series of long tunnels. The west portal of the tunnel lies at the eastern bank of the Komagome River in Aomori.

The completion of the tunnel and the subsequent extension of the Tōhoku Shinkansen to Aomori resulted in a decrease in the length of a trip from Tokyo to Aomori by 40 minutes and the elimination of the Tsugaru express train between Hachinohe and Aomori.[2]

History

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Background

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The Hakkōda Tunnel under construction

The Hakkōda Mountains have divided what is now Aomori Prefecture since the Edo period. The lands to the east of the mountains were controlled by the Nanbu clan and the lands to the west were controlled by the Tsugaru clan. After the Meiji Restoration, their lands were reorganized into Aomori Prefecture with the city of Aomori as its capital. However, no direct land route was available between and the former center of the Nanbu's Hachinohe Domain, Hachinohe because of the mountains. The Edo era Ōshū Kaidō instead went north around the mountain range, closely following the rocky coast in many places, such as Asamushi Onsen. When the Tōhoku Main Line was built to connect Aomori to Tokyo, the same indirect path was utilized.[3]

Efforts were still made to cross the Hakkōda Mountains. In an exercise to prepare for the destruction of the railway during a war with the Russian Empire, the Hakkōda Mountains incident occurred when 199 soldiers of the Imperial Japanese Army got lost and died, just south of where the tunnel now lies.[4]

The first direct connection between Aomori and Hachinohe, the Michinoku Toll Road, was completed on 13 November 1980. The toll road utilized many tunnels to cross the Hakkōda Mountains and set the precedent for a high-speed rail route to supplement it and the indirect Tōhoku Main Line.[5]

Construction

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Preliminary work on the tunnel began in August 1998, with ground broken in June 1999. On its breakthrough on 27 February 2005, it surpassed the Iwate-Ichinohe Tunnel of the same Tōhoku Shinkansen to become the world's longest terrestrial (land-based) tunnel. This record was surpassed only two months later by the Lötschberg Base Tunnel in Switzerland, and in turn by the Gotthard Base Tunnel when it opened in 2016. However, the Lötschberg Base Tunnel has only a single track for most of its length, while the Gotthard Base Tunnel has two single-track tubes, and therefore the Hakkōda Tunnel remains the longest double-tracked, single-tube terrestrial railway tunnel in the world.[6]

Opening

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Test runs of the Shinkansen in the tunnel commenced on 19 November 2010, an emergency evacuation of the train in the tunnel was exercised.[7] JR East's Tōhoku Shinkansen officially began services through the tunnel between Shichinohe-Towada Station and Shin-Aomori Station on 4 December 2010.[8]

References

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  1. ^ "北海道新幹線 最長トンネルさらに長く 工事計画変更" [Construction plan changed on the Hokkaido Shinkansen's longest tunnel] (in Japanese). 28 July 2016. Archived from the original on 28 July 2016. Retrieved 12 April 2020.
  2. ^ Takashi Kitagawa (March 2005). "Extending the Shinkansen Network" (PDF). Retrieved 12 April 2020.
  3. ^ "二十三番 安養寺夢宅寺(浅虫)" [23 Anyoji Temple Asamushi] (in Japanese). 27 February 2008. Archived from the original on 19 May 2018. Retrieved 12 April 2020.
  4. ^ Death March on Mount Hakkōda. Google Books. Retrieved on 10 November 2008.
  5. ^ "Michinoku Toll Road". Aomori Prefecture Road Corporation website. Retrieved 12 April 2020.
  6. ^ "Hakkoda Tunnel – The longest land-based double track tunnel in the world". The World's Greatest Japanese. 17 February 2008. Archived from the original on 13 July 2011. Retrieved 18 June 2010.
  7. ^ "〈青森・東京〉「道」は八甲田トンネルまで" [Aomori-Tokyo "Road" to Hakkōda Tunnel]. Asahi Shimbun (in Japanese). 8 November 2010. Retrieved 12 April 2020.
  8. ^ Misawa, Manabu (January 2010). 東北新幹線・九州新幹線 建設状況最新レポート. Tetsudō Daiya Jōhō Magazine. Vol. 39, no. 309. Japan: Kōtsū Shimbun. pp. 29–35.

Bibliography

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